SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96363a197085d62077425fe0af4853e17aaac3bdddacab29ba78a0a6425c9c73' 
  AND token = 'jz/8UvPeoUJdBT+KtA+rpMmhHvCDOzzYE6PwvNYCmG8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}